Adsorption effect on the successive ionic layer adsorption and reaction technique

We carried out a series of experiments of metal sulfide deposition on glass and copper substrates by the successive ionic layer adsorption and reaction (SILAR) technique. This technique based on the cations adsorption process involves the presence of the van der Waals and electrostatic forces. According to the theoretical study discussed herein, the equilibrium separation between cations and the substrate surface was lower in the case of a copper substrate than that of a glass one confirming the observed experiments results obtained by the SILAR technique. The surface charge of the glass substrate is strongly dependent on the solution pH. In the absence of the surface charge, the dominant forces between cations in solution and the glass substrate were repulsive in contrast with the case of the copper substrate in which attractive forces dominate even if the surface is somewhat positively charged. This study enriches the knowledge on the optimization parameters for fabricating thin films of metal chalcogenide of good adherence. © 2015, Allerton Press, Inc.